Couple stupid questions

[Gigas]

Ok I have a couple questions that I have to apologize if that seem stupid - but guess that's part of learning asking stupid questions This is for the lexus gs450H

First is the ignition switch - I'm building my car from an empty shell so it has no ignition so I was just going to use a push button start - The stupid question is does the need to be an open or closed connection? either it's pushed for a closed connection and keep everything on , push it again and it's now an open connection and everything is off. OR is this a push connection, it makes contact then opens - everything starts, push it again, makes contact everything is off?

Next stupid question is what is this stop L switch for - Is this just tied to your break pedal and when pushed it activates regen? as it looks like it just lets 12v pass through to activate that signal.

To round things up with my final stupid question is the drive selector component - again since I don't have one I figured I'd use something like this https://zero-ev.co.uk/product/gear-sele ... nversions/ but am actually unsure what this component actually is. It looks like it just creates a closed connection(12V) with the corresponding pin for Park, reverse and Drive

[TFirenza]

Ill try to answer but I may be wrong.
the first is example is just a basic switch when on the blue wires indicated have 12v,
second I believe is just the signal to the stop lights so the vcu could light them under regen ect.
third is the gear selector on the transmission side the lever arm feeds back a signal based on its position, you could wire this up or something else.

[ZooKeeper]

Ok I have a couple questions that I have to apologize if that seem stupid - but guess that's part of learning asking stupid questions This is for the lexus gs450H

The ONLY "stupid question" is the one unasked!

First is the ignition switch - I'm building my car from an empty shell so it has no ignition so I was just going to use a push button start - The stupid question is does the need to be an open or closed connection? either it's pushed for a closed connection and keep everything on , push it again and it's now an open connection and everything is off. OR is this a push connection, it makes contact then opens - everything starts, push it again, makes contact everything is off?

The answer is it can be either a toggle or push button, but must "latch" in position (closed or open).

Next stupid question is what is this stop L switch for - Is this just tied to your break pedal and when pushed it activates regen? as it looks like it just lets 12v pass through to activate that signal.

That is a momentary brake light switch, "L" is for light or lamp.

To round things up with my final stupid question is the drive selector component... but am actually unsure what this component actually is. It looks like it just creates a closed connection(12V) with the corresponding pin for Park, reverse and Drive

The 450h is a little outside my wheelhouse, but in any event the "drive" and "reverse" are controlled by the VCU (or more exactly the inverter). The signals needed are dependent on the "controller" used, in MY case, "latching switches" have been chosen. How the parking and high-low gear functions work, I will defer to someone who actually knows as I am not he

[Gigas]

second I believe is just the signal to the stop lights so the vcu could light them under regen ect.

That is a momentary brake light switch, "L" is for light or lamp.

GS450H Wiring overview V2.4.pdf

(947.8 KiB) Downloaded 178 times

Ok I'm sure I missing something simple but according to the diagram the brake light switch could turn on the brake lights but there are no lights attached to the VCU or a signal to them so I can't see what this would do other then just tell the vcu that it's braking - is that right? is the intent to send the signals out via pin 18 and 19 CAN to something in the current car then will then turn on the brakes via can signal? Since I'm an empty shell I guess I just tie the momentary switch to a relay to control brakes that way if that's the case.

third is the gear selector on the transmission side the lever arm feeds back a signal based on its position, you could wire this up or something else.

The 450h is a little outside my wheelhouse, but in any event the "drive" and "reverse" are controlled by the VCU (or more exactly the inverter). The signals needed are dependent on the "controller" used, in MY case, "latching switches" have been chosen. How the parking and high-low gear functions work, I will defer to someone who actually knows as I am not he

So is this a connection already on the transmission? I just got this transmission and havn't had a free second to go over it due to work and the holidays or is this a external device like I linked in the above post. I will eventual start a build thread but just getting me head around every aspect before I start fleshing things out

[TFirenza]

yeah there is a lever and a socket for position signal, probably best going through Damien's deep dive video

[Gigas]

yeah there is a lever and a socket for position signal, probably best going through Damien's deep dive video

I've watched that a bit ago I must have missed it - i'll watch again

[TFirenza]

This is the socket

[Gigas]

This is the socket

so now that i'm looking at it - is the mechanic level mechanically switching it and the connection is then telling the VCU what direction it needs to go?

[sfk]

The gear shift lever inside the car is connected to a metal rod which is attached to the arm of the mechanical switch in the photo posted above. The position is encoded and sent through the wire back to the VCU. Why on earth they didn't just encode this signal at the gear select lever and send directly to the VCU is not known. I imagine it's because they wanted to use 1 setup for all versions of this car's drivetrain, including the non hybrid ones. But still, no transmissions require a physical rod connection to shift drive modes now. They're all electronically shifted aren't they? Perhaps it creates the right kind of "shift feel" that people like??

[Gigas]

The gear shift lever inside the car is connected to a metal rod which is attached to the arm of the mechanical switch in the photo posted above. The position is encoded and sent through the wire back to the VCU. Why on earth they didn't just encode this signal at the gear select lever and send directly to the VCU is not known. I imagine it's because they wanted to use 1 setup for all versions of this car's drivetrain, including the non hybrid ones. But still, no transmissions require a physical rod connection to shift drive modes now. They're all electronically shifted aren't they? Perhaps it creates the right kind of "shift feel" that people like??

So you need to use the mechanical switch to then tell the VCU and the transmission what to do. kind of seems redundant if I understand that correctly. Anyone know how park is handled? is there a mechanical lock like in a leaf motor gearbox?

[slow67]

The GS450h does have a mechanical parking pawl actuated buy the mechanical linkage like a traditional automatic transmission

[sfk]

Well there you go. They do have a purpose for it.

[Gigas]

Well there you go. They do have a purpose for it.

I'll just to click it in places and see what happens i guess

[Gigas]

yeah there is a lever and a socket for position signal, probably best going through Damien's deep dive video

Now I just need to figure out what the brake light switch actually does - other then just tell the VCU it's "braking" because I don't see any way of connecting lights or the like